fscat_vxfs(ADM)


fscat_vxfs - cat a VERITAS File System

Synopsis

fscat [-F vxfs] [-o offset] [-l length] [-b block_size] [-f output_file] special

Description

The fscat utility provides an interface to a vxfs snapshot file system similar to that provided by the dd(ADM) utility invoked on the special file of other vxfs file systems.

On most vxfs file systems, the block or character special file for the file system provides access to a raw image of the file system for purposes such as backing up the file system to tape. On a snapshot file system, access to the corresponding block or character special provides little useful information. The fscat utility, however, provides a stream of bytes representing the file system snapshot. The datastream is written by default to standard output, although the -f output_file option can be used to specify another destination. The datastream on standard output can be processed in any of several ways, such as being processed in a pipeline, being written to a tape, and so on. fscat will work when executed on the special device of any vxfs file system.

By default, the output is a stream of bytes that starts at the beginning of the file system and goes to the end. On a snapshot file system, data is read from the file system using special ioctls on the mount point. On other vxfs file systems, data is read from the specified special file. Unless otherwise specified, data is written to standard output.

All numbers entered as options may have 0 prepended to indicate octal, or 0x prepended to indicate hexadecimal. A b or B may be appended to indicate the value is in 512-byte blocks, a k or K to indicate the value is in kilobytes, an m or M to indicate the value is in megabytes or a g or G to indicate the value is in gigabytes. An appended letter may be separated from the number by a space, in which case the letter and number should be enclosed in a set of quotes (for example, "512 b").

All numbers entered as options must be in multiples of 512 bytes. So, for example, a value of 5713 as an offset will be rejected.

Options

-F vxfs
Specify a vxfs file system type.

-o offset
Specify the starting offset, in bytes.

-l length
Specify the length, in bytes. A length of 0 goes to the end of the file system.

-b block_size
Specify the output block size, in bytes. block_size must be less than or equal to 1 megabyte.

-f output_file
Specify an output file into which the datastream is to be written.

Notices

fscat is available with the VxFS Advanced feature set only.

A snapshot file system cannot be written to. A snapshot file system exists only as long as it is mounted; once unmounted, the special file no longer contains a snapshot file system.

References

dd(ADM), fs_vxfs(F), vxfsio(HW)



© 1997 The Santa Cruz Operation, Inc. All rights reserved.